It is proposed in this supplement to design, construct, test and utilize a fission fragment ionization mass spectrometer to be used for the analysis of involatile, chemically fragile materials of biomedical interest. The volatilization and ionization of the sample will be effected by bombarding it with fission fragments emitted by Californium-252 (252Cf). Mass analysis will be effected by a high resolution time of flight technique. Typical compound types to be investigated will be peptides, nucleotides, polysaccharides, quaternary amines, ionic materials, and the like.